SOLUTION: I need help finding the domain of this equation through algebra. The function is: {{{ sqrt(x)/(x^2-9) }}} thank you in advance!

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Question 220503: I need help finding the domain of this equation through algebra.
The function is:
+sqrt%28x%29%2F%28x%5E2-9%29+
thank you in advance!

Found 2 solutions by rapaljer, jim_thompson5910:
Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
There are TWO restrictions here. First of all, the denominator must NEVER equal zero, so x cannot equal 3 or -3.

Secondly, because of the sqrt%28x%29, x must be greater than or equal to zero!

Now, take the intersection of these two requirements, and you have all values greater than or equal to zero, except x=3. In interval notation, this would be
[0,3)U (3, inf)

R^2

Dr. Robert J. Rapalje

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Here are some key things to remember:

1) You cannot take the square root of a negative number. So this means that sqrt%28x%29 forces x to be positive or zero. This means that x%3E=0


2) You cannot divide by zero. So x%5E2-9%3C%3E0 (ie the denominator can't be zero). This means that x%3C%3E-3 or x%3C%3E3 (these values would make the denominator equal to zero. Since x%3E=0, we don't need to worry about x%3C%3E-3

Putting 1) and 2) together gets us the domain (in interval notation): [)()


This basically says that the domain is any non-negative number but x%3C%3E3